Pore-forming toxins (PFTs) are abundant bacterial virulence factors that play a role in infections by numerous problematic pathogens and are potential targets in the search for novel antimicrobial therapeutics. PFTs perforate host cell membranes, allowing bacteria to evade the immune system and spread within the host. Host cells in turn employ defense pathways to survive and repair their cell membranes. Besides disabling PFT function, PFT-targeting strategies may include the priming or boosting of host defenses. Activity and expression of NR4A-family orphan nuclear receptors, which we have identified as novel PFT defense factors, can be manipulated in vitro and in vivo by small compounds. We propose two specific aims directed at elucidating the molecular mechanisms of how NR4As defend against PFTs and intact pathogens using multiple model systems and at applying this new knowledge as a new therapeutic strategy for identifying small compounds to treat and prevent important infectious diseases.

Public Health Relevance

Many bacteria that cause serious infections in humans make pore-forming toxins, which can damage human cells and which are required for infection to occur. In this proposal, we will test new methods for understanding how human cells can be defended against such toxins and will evaluate drug candidates for bolstering such protection. Successful completion of these studies will further the search for new classes of drugs to prevent and treat infectious diseases.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Exploratory/Developmental Grants (R21)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-IDM-B (80))
Program Officer
Huntley, Clayton C
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Columbia University (N.Y.)
Schools of Medicine
New York
United States
Zip Code
LaRocca, Timothy J; Sosunov, Sergey A; Shakerley, Nicole L et al. (2016) Hyperglycemic Conditions Prime Cells for RIP1-dependent Necroptosis. J Biol Chem 291:13753-61
Amaral, Fábio E; Parker, Dane; Randis, Tara M et al. (2015) Rational manipulation of mRNA folding free energy allows rheostat control of pneumolysin production by Streptococcus pneumoniae. PLoS One 10:e0119823
LaRocca, T J; Stivison, E A; Mal-Sarkar, T et al. (2015) CD59 signaling and membrane pores drive Syk-dependent erythrocyte necroptosis. Cell Death Dis 6:e1773
LaRocca, Timothy J; Stivison, Elizabeth A; Hod, Eldad A et al. (2014) Human-specific bacterial pore-forming toxins induce programmed necrosis in erythrocytes. MBio 5:e01251-14
Randis, Tara M; Gelber, Shari E; Hooven, Thomas A et al. (2014) Group B Streptococcus β-hemolysin/cytolysin breaches maternal-fetal barriers to cause preterm birth and intrauterine fetal demise in vivo. J Infect Dis 210:265-73
Los, Ferdinand C O; Randis, Tara M; Aroian, Raffi V et al. (2013) Role of pore-forming toxins in bacterial infectious diseases. Microbiol Mol Biol Rev 77:173-207